Try running a benchmark (under the Help menu) and pasting the results here. It's possible you could improve it by reducing the framerate that Theater View uses. Theater uses 3D drawing and it's expensive.
Theater View isn't lagging like in being "choppy". It rather lags substantially behind my finger when I'm scrolling up and down. It's difficult to explain but it's a very different and less responsive touch experience compared to most other touch supported programs and especially modern apps. Like if you had a thick screen protector applied (which I don't).
Nevertheless, I'm more than ready to experiment. I run Theater View on three different tablets - this benchmark is from my Surface Pro 4:
=== Running Benchmarks (please do not interrupt) ===
Running 'Math' benchmark...
Single-threaded integer math... 5,404 seconds
Single-threaded floating point math... 3,737 seconds
Multi-threaded integer math... 3,014 seconds
Multi-threaded mixed math... 2,067 seconds
Score: 1336
Running 'Image' benchmark...
Image creation / destruction... 0,683 seconds
Flood filling... 0,321 seconds
Direct copying... 0,481 seconds
Small renders... 1,801 seconds
Bilinear rendering... 1,653 seconds
Bicubic rendering... 1,005 seconds
Score: 3701
Running 'Database' benchmark...
Create database... 0,268 seconds
Populate database... 1,580 seconds
Save database... 0,451 seconds
Reload database... 0,098 seconds
Search database... 1,440 seconds
Sort database... 1,377 seconds
Group database... 0,810 seconds
Score: 3569
JRMark (version 21.0.90): 2869